For example: a Progenitor b1 Child c1 Grandchild d1 Great-grandchild d2 Great-grandchild c2 Grandchild c3 Grandchild b2 Child c1 Grandchild d1 Great-grandchild d2 Great-grandchild d3 Great-grandchild c2 Grandchild c3 Grandchild In this system, b2.c3 is the third child of the second child, and is one of the progenitor's grandchildren. The de Villiers/Pama system is the standard for genealogical works in South Africa. It was developed in the 19th century by Christoffel Coetzee de Villiers and used in his three volume Geslachtregister der Oude Kaapsche Familien (Genealogies of Old Cape Families). The system was refined by Dr. Cornelis (Cor) Pama, one of the founding members of the Genealogical Society of South Africa. See also Ancestral File Number Ahnentafel Cousin chart (Table of consanguinity) Family tree Family tree mapping GEDCOM Genogram Kinship terminology Pedigree chart Pedigree collapse Numerical variation in kinship terms References Sources About.com: Numbering Your Family Tree Numbering Systems in Genealogy by Richard A. Pence External links Encyclopedia of Genealogy-Numbering Systems Numbering Systems in Genealogy Genealogy Genealogy